Mobility aid



FIG. 1 is a perspective view embodying the inventive design;

FIG. 2 is another perspective view thereof;

FIG. 3 is a left view thereof;

FIG. 4 is a front side thereof

FIG. 5 is a right view thereof;

FIG. 6 is a rear view thereof;

FIG. 7 is a top view thereof; and,

FIG. 8 is a bottom view thereof.

The broken lines are directed to environment and form no part of the claimed design. 

CLAIM The ornamental design for a mobility aid, as shown and described. 